The MP4 extension is only a container for the video file. Meaning that various codecs can be used with the MP4 container. This is usually worked around by installing the codec on the system that is sharing the video out and sometimes the ones viewing the share. We noticed this fixed the issue on Windows XP but after extensive testing\research we were unable to resolve the issue with Windows 7.

Perhaps a better way of listing what videos we support would be to list the codecs we support.

We are definitely continuing to look for a solution and will touch base when we have one.